From fd8d6b1590a9833973b0b470ae2e0c35430f34f0 Mon Sep 17 00:00:00 2001
From: Dave Townsend <dtownsend@oxymoronical.com>
Date: Wed, 15 Aug 2018 10:31:16 +0000
Subject: [PATCH] Bug 1480465: Infer the namespace for custom elements at
 definition time by following the class hierarchy. r=smaug

When a custom element is defined we can check whether its class is an instance
of XULElement or HTMLElement and tag the defintion with a namespace accordingly.
This allows us to know the correct namespace for the custom element when
created.

Differential Revision: https://phabricator.services.mozilla.com/D2680

--HG--
extra : moz-landing-system : lando
---
 dom/base/CustomElementRegistry.cpp            |  28 ++++-
 dom/base/CustomElementRegistry.h              |   8 +-
 dom/base/nsContentUtils.cpp                   |  11 +-
 dom/bindings/BindingUtils.cpp                 |   5 +-
 .../webcomponents/chrome_disabled.ini         |   3 +
 .../test_custom_element_namespace.html        |  95 +++++++++++++++
 .../test_custom_element_namespace.xhtml       | 104 ++++++++++++++++
 .../test_custom_element_namespace.xul         | 112 ++++++++++++++++++
 parser/html/nsHtml5TreeOperation.cpp          |   2 +-
 9 files changed, 359 insertions(+), 9 deletions(-)
 create mode 100644 dom/tests/mochitest/webcomponents/test_custom_element_namespace.html
 create mode 100644 dom/tests/mochitest/webcomponents/test_custom_element_namespace.xhtml
 create mode 100644 dom/tests/mochitest/webcomponents/test_custom_element_namespace.xul

diff --git a/dom/base/CustomElementRegistry.cpp b/dom/base/CustomElementRegistry.cpp
index d6b7821dbd1a..781ca153c625 100644
--- a/dom/base/CustomElementRegistry.cpp
+++ b/dom/base/CustomElementRegistry.cpp
@@ -10,6 +10,7 @@
 #include "mozilla/CycleCollectedJSContext.h"
 #include "mozilla/dom/CustomElementRegistryBinding.h"
 #include "mozilla/dom/HTMLElementBinding.h"
+#include "mozilla/dom/XULElementBinding.h"
 #include "mozilla/dom/Promise.h"
 #include "mozilla/dom/WebComponentsBinding.h"
 #include "mozilla/dom/DocGroup.h"
@@ -356,6 +357,7 @@ CustomElementRegistry::RunCustomElementCreationCallback::Run()
 
 CustomElementDefinition*
 CustomElementRegistry::LookupCustomElementDefinition(nsAtom* aNameAtom,
+                                                     int32_t aNameSpaceID,
                                                      nsAtom* aTypeAtom)
 {
   CustomElementDefinition* data = mCustomDefinitions.GetWeak(aTypeAtom);
@@ -373,7 +375,7 @@ CustomElementRegistry::LookupCustomElementDefinition(nsAtom* aNameAtom,
     }
   }
 
-  if (data && data->mLocalName == aNameAtom) {
+  if (data && data->mLocalName == aNameAtom && data->mNamespaceID == aNameSpaceID) {
     return data;
   }
 
@@ -688,6 +690,24 @@ CustomElementRegistry::GetDocGroup() const
   return mWindow ? mWindow->GetDocGroup() : nullptr;
 }
 
+int32_t
+CustomElementRegistry::InferNamespace(JSContext* aCx,
+                                      JS::Handle<JSObject*> constructor)
+{
+  JSObject* XULConstructor = XULElement_Binding::GetConstructorObject(aCx);
+
+  JS::Rooted<JSObject*> proto(aCx, constructor);
+  while (proto) {
+    if (proto == XULConstructor) {
+      return kNameSpaceID_XUL;
+    }
+
+    JS_GetPrototype(aCx, proto, &proto);
+  }
+
+  return kNameSpaceID_XHTML;
+}
+
 // https://html.spec.whatwg.org/multipage/scripting.html#element-definition
 void
 CustomElementRegistry::Define(JSContext* aCx,
@@ -720,12 +740,13 @@ CustomElementRegistry::Define(JSContext* aCx,
     return;
   }
 
+  int32_t nameSpaceID = InferNamespace(aCx, constructor);
+
   /**
    * 2. If name is not a valid custom element name, then throw a "SyntaxError"
    *    DOMException and abort these steps.
    */
   nsIDocument* doc = mWindow->GetExtantDoc();
-  uint32_t nameSpaceID = doc ? doc->GetDefaultNamespaceID() : kNameSpaceID_XHTML;
   RefPtr<nsAtom> nameAtom(NS_Atomize(aName));
   if (!nsContentUtils::IsCustomElementName(nameAtom, nameSpaceID)) {
     aRv.Throw(NS_ERROR_DOM_SYNTAX_ERR);
@@ -945,6 +966,7 @@ CustomElementRegistry::Define(JSContext* aCx,
   RefPtr<CustomElementDefinition> definition =
     new CustomElementDefinition(nameAtom,
                                 localNameAtom,
+                                nameSpaceID,
                                 &aFunctionConstructor,
                                 std::move(observedAttributes),
                                 std::move(callbacksHolder));
@@ -1471,11 +1493,13 @@ NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(CustomElementDefinition, Release)
 
 CustomElementDefinition::CustomElementDefinition(nsAtom* aType,
                                                  nsAtom* aLocalName,
+                                                 int32_t aNamespaceID,
                                                  Function* aConstructor,
                                                  nsTArray<RefPtr<nsAtom>>&& aObservedAttributes,
                                                  UniquePtr<LifecycleCallbacks>&& aCallbacks)
   : mType(aType),
     mLocalName(aLocalName),
+    mNamespaceID(aNamespaceID),
     mConstructor(new CustomElementConstructor(aConstructor)),
     mObservedAttributes(std::move(aObservedAttributes)),
     mCallbacks(std::move(aCallbacks))
diff --git a/dom/base/CustomElementRegistry.h b/dom/base/CustomElementRegistry.h
index 8f28fa2ae920..2886ae5a63dd 100644
--- a/dom/base/CustomElementRegistry.h
+++ b/dom/base/CustomElementRegistry.h
@@ -157,6 +157,7 @@ struct CustomElementDefinition
 
   CustomElementDefinition(nsAtom* aType,
                           nsAtom* aLocalName,
+                          int32_t aNamespaceID,
                           Function* aConstructor,
                           nsTArray<RefPtr<nsAtom>>&& aObservedAttributes,
                           UniquePtr<LifecycleCallbacks>&& aCallbacks);
@@ -168,6 +169,9 @@ struct CustomElementDefinition
   // The localname to (e.g. <button is=type> -- this would be button).
   RefPtr<nsAtom> mLocalName;
 
+  // The namespace for this custom element
+  int32_t mNamespaceID;
+
   // The custom element constructor.
   RefPtr<CustomElementConstructor> mConstructor;
 
@@ -399,7 +403,7 @@ public:
    * https://html.spec.whatwg.org/#look-up-a-custom-element-definition
    */
   CustomElementDefinition* LookupCustomElementDefinition(
-    nsAtom* aNameAtom, nsAtom* aTypeAtom);
+    nsAtom* aNameAtom, int32_t aNameSpaceID, nsAtom* aTypeAtom);
 
   CustomElementDefinition* LookupCustomElementDefinition(
     JSContext* aCx, JSObject *aConstructor) const;
@@ -555,6 +559,8 @@ private:
       CustomElementRegistry* mRegistry;
   };
 
+  int32_t InferNamespace(JSContext* aCx, JS::Handle<JSObject*> constructor);
+
 public:
   nsISupports* GetParentObject() const;
 
diff --git a/dom/base/nsContentUtils.cpp b/dom/base/nsContentUtils.cpp
index 44e772461c0b..3a0747340b5a 100644
--- a/dom/base/nsContentUtils.cpp
+++ b/dom/base/nsContentUtils.cpp
@@ -10002,6 +10002,15 @@ nsContentUtils::NewXULOrHTMLElement(Element** aResult, mozilla::dom::NodeInfo* a
     nsIGlobalObject* global;
     if (aFromParser == dom::NOT_FROM_PARSER) {
       global = GetEntryGlobal();
+
+      // XUL documents always use NOT_FROM_PARSER for non-XUL elements. We can
+      // get the global from the document in that case.
+      if (!global) {
+        nsIDocument* doc = nodeInfo->GetDocument();
+        if (doc && doc->IsXULDocument()) {
+          global = doc->GetScopeObject();
+        }
+      }
     } else {
       global = nodeInfo->GetDocument()->GetScopeObject();
     }
@@ -10122,7 +10131,7 @@ nsContentUtils::LookupCustomElementDefinition(nsIDocument* aDoc,
     return nullptr;
   }
 
-  return registry->LookupCustomElementDefinition(aNameAtom, aTypeAtom);
+  return registry->LookupCustomElementDefinition(aNameAtom, aNameSpaceID, aTypeAtom);
 }
 
 /* static */ void
diff --git a/dom/bindings/BindingUtils.cpp b/dom/bindings/BindingUtils.cpp
index fc82c0acab3c..027928a4db69 100644
--- a/dom/bindings/BindingUtils.cpp
+++ b/dom/bindings/BindingUtils.cpp
@@ -3811,10 +3811,7 @@ HTMLConstructor(JSContext* aCx, unsigned aArgc, JS::Value* aVp,
   // determination of what sort of element we're planning to construct.
   // Technically, this should happen (implicitly) in step 8, but this
   // determination is side-effect-free, so it's OK.
-  int32_t ns = doc->GetDefaultNamespaceID();
-  if (ns != kNameSpaceID_XUL) {
-    ns = kNameSpaceID_XHTML;
-  }
+  int32_t ns = definition->mNamespaceID;
 
   constructorGetterCallback cb = nullptr;
   if (ns == kNameSpaceID_XUL) {
diff --git a/dom/tests/mochitest/webcomponents/chrome_disabled.ini b/dom/tests/mochitest/webcomponents/chrome_disabled.ini
index 91a399a31c3b..0a9027e309b5 100644
--- a/dom/tests/mochitest/webcomponents/chrome_disabled.ini
+++ b/dom/tests/mochitest/webcomponents/chrome_disabled.ini
@@ -3,3 +3,6 @@ prefs =
   dom.webcomponents.customelements.enabled=false
 
 [test_xul_custom_element.xul]
+[test_custom_element_namespace.html]
+[test_custom_element_namespace.xhtml]
+[test_custom_element_namespace.xul]
diff --git a/dom/tests/mochitest/webcomponents/test_custom_element_namespace.html b/dom/tests/mochitest/webcomponents/test_custom_element_namespace.html
new file mode 100644
index 000000000000..fa1e91b57331
--- /dev/null
+++ b/dom/tests/mochitest/webcomponents/test_custom_element_namespace.html
@@ -0,0 +1,95 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Custom Elements in an HTML document</title>
+  <script type="text/javascript" src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css" />
+  <script>
+    SimpleTest.waitForExplicitFinish();
+
+    const HTML_NS = "http://www.w3.org/1999/xhtml";
+    const XUL_NS = "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
+
+    class TestXULCustomElement extends XULElement {
+      constructor() {
+        super();
+      }
+
+      get connected() {
+        return true;
+      }
+    }
+
+    customElements.define("test-xul-element", TestXULCustomElement);
+
+    class TestHTMLCustomElement extends HTMLElement {
+      constructor() {
+        super();
+      }
+
+      get connected() {
+        return true;
+      }
+    }
+
+    customElements.define("test-html-element", TestHTMLCustomElement);
+
+    function checkElement(element, ns, connected, type) {
+      is(element.namespaceURI, ns, `${type} should have the correct namespace`);
+      if (connected) {
+        ok(element.connected, `${type} should have applied the class`);
+      } else {
+        is(element.connected, undefined, `${type} should not have applied the class`);
+      }
+    }
+
+    function runTest() {
+      let element = new TestXULCustomElement();
+      checkElement(element, XUL_NS, true, "instantiated XUL");
+
+      element = document.getElementById("xul2");
+      checkElement(element, HTML_NS, false, "parsed XUL as HTML");
+
+      element = document.createElement("test-xul-element");
+      checkElement(element, HTML_NS, false, "document.createElement(XUL)");
+
+      element = document.createXULElement("test-xul-element");
+      checkElement(element, XUL_NS, true, "document.createXULElement(XUL)");
+
+      element = document.createElementNS(XUL_NS, "test-xul-element");
+      checkElement(element, XUL_NS, true, "document.createElementNS(XUL, XUL)");
+
+      element = document.createElementNS(HTML_NS, "test-xul-element");
+      checkElement(element, HTML_NS, false, "document.createElementNS(HTML, XUL)");
+
+      element = new TestHTMLCustomElement();
+      checkElement(element, HTML_NS, true, "instantiated HTML");
+
+      element = document.getElementById("html2");
+      checkElement(element, HTML_NS, true, "parsed HTML as HTML");
+
+      element = document.createElement("test-html-element");
+      checkElement(element, HTML_NS, true, "document.createElement(HTML)");
+
+      element = document.createXULElement("test-html-element");
+      checkElement(element, XUL_NS, false, "document.createXULElement(HTML)");
+
+      element = document.createElementNS(XUL_NS, "test-html-element");
+      checkElement(element, XUL_NS, false, "document.createElementNS(XUL, HTML)");
+
+      element = document.createElementNS(HTML_NS, "test-html-element");
+      checkElement(element, HTML_NS, true, "document.createElementNS(HTML, HTML)");
+
+      SimpleTest.finish();
+    }
+  </script>
+</head>
+<body onload="runTest();">
+  <p id="display"></p>
+  <div id="content">
+    <test-xul-element id="xul2"/>
+    <test-html-element id="html2"/>
+  </div>
+  <pre id="test"></pre>
+</body>
+</html>
diff --git a/dom/tests/mochitest/webcomponents/test_custom_element_namespace.xhtml b/dom/tests/mochitest/webcomponents/test_custom_element_namespace.xhtml
new file mode 100644
index 000000000000..b25e6110aec1
--- /dev/null
+++ b/dom/tests/mochitest/webcomponents/test_custom_element_namespace.xhtml
@@ -0,0 +1,104 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<html xmlns="http://www.w3.org/1999/xhtml">
+<head>
+  <title>Custom Elements in an XHTML document</title>
+  <script type="text/javascript" src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css" />
+  <script>
+    SimpleTest.waitForExplicitFinish();
+
+    const HTML_NS = "http://www.w3.org/1999/xhtml";
+    const XUL_NS = "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
+
+    class TestXULCustomElement extends XULElement {
+      constructor() {
+        super();
+      }
+
+      get connected() {
+        return true;
+      }
+    }
+
+    customElements.define("test-xul-element", TestXULCustomElement);
+
+    class TestHTMLCustomElement extends HTMLElement {
+      constructor() {
+        super();
+      }
+
+      get connected() {
+        return true;
+      }
+    }
+
+    customElements.define("test-html-element", TestHTMLCustomElement);
+
+    function checkElement(element, ns, connected, type) {
+      is(element.namespaceURI, ns, `${type} should have the correct namespace`);
+      if (connected) {
+        ok(element.connected, `${type} should have applied the class`);
+      } else {
+        is(element.connected, undefined, `${type} should not have applied the class`);
+      }
+    }
+
+    function runTest() {
+      let element = new TestXULCustomElement();
+      checkElement(element, XUL_NS, true, "instantiated XUL");
+
+      element = document.getElementById("xul1");
+      checkElement(element, XUL_NS, true, "parsed XUL as XUL");
+
+      element = document.getElementById("xul2");
+      checkElement(element, HTML_NS, false, "parsed XUL as HTML");
+
+      element = document.createElement("test-xul-element");
+      checkElement(element, HTML_NS, false, "document.createElement(XUL)");
+
+      element = document.createXULElement("test-xul-element");
+      checkElement(element, XUL_NS, true, "document.createXULElement(XUL)");
+
+      element = document.createElementNS(XUL_NS, "test-xul-element");
+      checkElement(element, XUL_NS, true, "document.createElementNS(XUL, XUL)");
+
+      element = document.createElementNS(HTML_NS, "test-xul-element");
+      checkElement(element, HTML_NS, false, "document.createElementNS(HTML, XUL)");
+
+      element = new TestHTMLCustomElement();
+      checkElement(element, HTML_NS, true, "instantiated HTML");
+
+      element = document.getElementById("html1");
+      checkElement(element, XUL_NS, false, "parsed HTML as XUL");
+
+      element = document.getElementById("html2");
+      checkElement(element, HTML_NS, true, "parsed HTML as HTML");
+
+      element = document.createElement("test-html-element");
+      checkElement(element, HTML_NS, true, "document.createElement(HTML)");
+
+      element = document.createXULElement("test-html-element");
+      checkElement(element, XUL_NS, false, "document.createXULElement(HTML)");
+
+      element = document.createElementNS(XUL_NS, "test-html-element");
+      checkElement(element, XUL_NS, false, "document.createElementNS(XUL, HTML)");
+
+      element = document.createElementNS(HTML_NS, "test-html-element");
+      checkElement(element, HTML_NS, true, "document.createElementNS(HTML, HTML)");
+
+      SimpleTest.finish();
+    }
+  </script>
+</head>
+<body onload="runTest();">
+  <p id="display"></p>
+  <div id="content">
+    <test-xul-element xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" id="xul1"/>
+    <test-html-element xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" id="html1"/>
+    <test-xul-element id="xul2"/>
+    <test-html-element id="html2"/>
+  </div>
+  <pre id="test"></pre>
+</body>
+</html>
diff --git a/dom/tests/mochitest/webcomponents/test_custom_element_namespace.xul b/dom/tests/mochitest/webcomponents/test_custom_element_namespace.xul
new file mode 100644
index 000000000000..32216afaa60c
--- /dev/null
+++ b/dom/tests/mochitest/webcomponents/test_custom_element_namespace.xul
@@ -0,0 +1,112 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css" type="text/css"?>
+
+<window title="XUL Custom Elements"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        onload="runTest();">
+  <title>Custom Elements in a XUL document</title>
+
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+
+  <script type="application/javascript">
+  <![CDATA[
+    SimpleTest.waitForExplicitFinish();
+
+    const HTML_NS = "http://www.w3.org/1999/xhtml";
+    const XUL_NS = "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
+
+    class TestXULCustomElement extends XULElement {
+      constructor() {
+        super();
+      }
+
+      get connected() {
+        return true;
+      }
+    }
+
+    customElements.define("test-xul-element", TestXULCustomElement);
+
+    class TestHTMLCustomElement extends HTMLElement {
+      constructor() {
+        super();
+      }
+
+      get connected() {
+        return true;
+      }
+    }
+
+    customElements.define("test-html-element", TestHTMLCustomElement);
+
+    function checkElement(element, ns, connected, type) {
+      is(element.namespaceURI, ns, `${type} should have the correct namespace`);
+      if (connected) {
+        ok(element.connected, `${type} should have applied the class`);
+      } else {
+        is(element.connected, undefined, `${type} should not have applied the class`);
+      }
+    }
+
+    function runTest() {
+      let element = new TestXULCustomElement();
+      checkElement(element, XUL_NS, true, "instantiated XUL");
+
+      element = document.getElementById("xul1");
+      checkElement(element, XUL_NS, true, "parsed XUL as XUL");
+
+      element = document.getElementById("xul2");
+      checkElement(element, HTML_NS, false, "parsed XUL as HTML");
+
+      element = document.createElement("test-xul-element");
+      checkElement(element, XUL_NS, true, "document.createElement(XUL)");
+
+      element = document.createXULElement("test-xul-element");
+      checkElement(element, XUL_NS, true, "document.createXULElement(XUL)");
+
+      element = document.createElementNS(XUL_NS, "test-xul-element");
+      checkElement(element, XUL_NS, true, "document.createElementNS(XUL, XUL)");
+
+      element = document.createElementNS(HTML_NS, "test-xul-element");
+      checkElement(element, HTML_NS, false, "document.createElementNS(HTML, XUL)");
+
+      element = new TestHTMLCustomElement();
+      checkElement(element, HTML_NS, true, "instantiated HTML");
+
+      element = document.getElementById("html1");
+      checkElement(element, XUL_NS, false, "parsed HTML as XUL");
+
+      element = document.getElementById("html2");
+      checkElement(element, HTML_NS, true, "parsed HTML as HTML");
+
+      element = document.createElement("test-html-element");
+      checkElement(element, XUL_NS, false, "document.createElement(HTML)");
+
+      element = document.createXULElement("test-html-element");
+      checkElement(element, XUL_NS, false, "document.createXULElement(HTML)");
+
+      element = document.createElementNS(XUL_NS, "test-html-element");
+      checkElement(element, XUL_NS, false, "document.createElementNS(XUL, HTML)");
+
+      element = document.createElementNS(HTML_NS, "test-html-element");
+      checkElement(element, HTML_NS, true, "document.createElementNS(HTML, HTML)");
+
+      SimpleTest.finish();
+    }
+  ]]>
+  </script>
+
+  <test-xul-element id="xul1"/>
+  <test-html-element id="html1"/>
+
+  <body xmlns="http://www.w3.org/1999/xhtml">
+    <p id="display"></p>
+    <div id="content" style="display: none">
+      <test-xul-element id="xul2"/>
+      <test-html-element id="html2"/>
+    </div>
+    <pre id="test"></pre>
+  </body>
+</window>
diff --git a/parser/html/nsHtml5TreeOperation.cpp b/parser/html/nsHtml5TreeOperation.cpp
index 16289da6a028..133c8979d111 100644
--- a/parser/html/nsHtml5TreeOperation.cpp
+++ b/parser/html/nsHtml5TreeOperation.cpp
@@ -382,7 +382,7 @@ nsHtml5TreeOperation::CreateHTMLElement(
   dom::CustomElementDefinition* definition = nullptr;
 
   // Avoid overhead by checking if custom elements pref is enabled or not.
-  if (nsContentUtils::IsCustomElementsEnabled()) {
+  if (dom::CustomElementRegistry::IsCustomElementEnabled(document)) {
     if (aAttributes) {
       nsHtml5String is = aAttributes->getValue(nsHtml5AttributeName::ATTR_IS);
       if (is) {